const lightDecorator:MethodDecorator = (target:Object, propertyKey:string | symbol,descriptor:PropertyDescriptor) => {
    const method = descriptor.value;
    descriptor.value = () => {
        return `<div style="color:red;">${method()}</div>`;
    }
}

class User{
    @lightDecorator
    public response(){
        return 'houdunren.com';
    }
}

document.body.insertAdjacentHTML('beforeend',new User().response());
